Microchannel structure body

ABSTRACT

A fine channel device, having an inlet opening for introducing a gas and an inlet path interconnecting with this inlet opening, a fine channel interconnecting with the inlet path, a discharge path interconnecting with the fine channel, and a discharge opening interconnecting with this discharge path. The inner diameter of the inlet path is greater than that of the fine channel, and either increases gradually, or remains identical, with increasing distance from the position where the inlet opening and the inlet path are in interconnection with each other.

TECHNICAL FIELD

The present invention relates to a fine channel device and a gastreatment apparatus. Priority is claimed on Japanese Patent ApplicationNo. 2003-075899, filed Mar. 19, 2003, the content of which isincorporated herein by reference.

BACKGROUND ART

In recent years, much attention has been focused on research using finechannel devices, wherein fine channels with a length of several cm, anda width and depth within a range from the sub-micron level to severalhundreds of μm are formed on top of a square glass substrate with a sidedimension of several cm, and chemical reactions are then conducted byintroducing fluids into these fine channels. Due to the effects ofshorter intermolecular distances within the microspaces, and largerspecific interfacial area, these fine channels enable highly efficientchemical reactions to be conducted (for example, see H. Hisamoto et al.,Fast and high conversion phase-transfer synthesis exploiting theliquid-liquid interface formed in a fine channel chip, Chem. Commun.,2001, pp. 2662 to 2663).

Tests are also being conducted into the industrial utilization ofchemical reactions within fine channels, while still retaining theinherent characteristics of these types of microspaces. In such cases,because of the small size of the microspace, the production volume ordischarge volume per unit of time from a single fine channel isnecessarily small. However, if a plurality of fine channels can bearranged in parallel, then the production volume or discharge volume perunit of time can be increased, while still retaining the characteristicsof the fine channels. Accordingly, tests have been conducted in which,for example, a plurality of fine channel substrates each containing asingle fine channel are prepared, and these substrates are thenlaminated together, with common portions such as the reaction solutioninlets or reaction product outlets interconnecting via vertical throughholes (for example, see Japanese Unexamined Patent Application, FirstPublication No. 2002-292275).

It is said that conducting large scale chemical reactions in thismanner, while retaining the characteristics of the microspaces, ispossible by either increasing the degree of integration of finechannels, which represent the minimum unit, in the planar direction, orlaminating substrates together three dimensionally. However,conventionally, distributing fluids equally to fine channels arranged ineither a planar or three dimensional structure has proven to beextremely difficult.

Furthermore, in the preparation of typical semiconductor devices, testshave been conducted in which, during a film formation process such asCVD (chemical vapor deposition) for forming a thin film of a differentmaterial from the base material on top of a base material such as Si,which is the most representative semiconductor substrate material, a gassuch as N₂O or NH₃ is activated using either a plasma or a heated metalcatalyst, and then used to dope the semiconductor base material, therebyforming a thin film of SiN or the like (for example, see JapaneseUnexamined Patent Application, First Publication No. Hei 10-83988).

However, methods that use a plasma require the generation of very highvoltages of several dozen KV or higher, meaning the apparatus tend to bevery large. Furthermore, generation of interface defects caused by theinjection into the semiconductor substrate material of high-energycharged particles generated within the plasma is unavoidable. Methodsthat use a heated metal catalyst require heating to very hightemperatures. For example, the activation of NH₃ requires heating to atleast 1600° C. Semiconductor film formation apparatus typically usequartz glass tube or glass boats. However, because the softening pointof quartz, which is the temperature at which the quartz begins to expandat a rate of 1 mm per minute, is approximately 1600 to 1700° C., quartzcontainers cannot be used. Accordingly, special containers made fromhighly heat resistant ceramic are necessary.

The present invention takes the conventional situation described aboveinto consideration, with an object of providing a fine channel device inwhich fluids can be distributed equally to a plurality of fine channelsdisposed in either a planar or three dimensional arrangement.Furthermore, the invention also provides a gas treatment apparatus thatuses this fine channel device, and enables the treatment of gases,including activation, decomposition, mixing, and reaction and the like,to be conducted more efficiently than has conventionally been possible.The term “treatment” in gas treatment apparatus refers to treatmentssuch as the activation or decomposition of a fluid, or the mixing orreaction of a plurality of gases.

DISCLOSURE OF INVENTION

The present invention provides a fine channel device comprising at leastone inlet opening for introducing a gas, at least one inlet pathinterconnecting with the inlet opening, at least one fine channel, whichinterconnects with the inlet path and distributes and feeds the gasequally, a discharge path which interconnects with the fine channel anddischarges the gas, and at least one discharge opening interconnectingwith the discharge path; wherein an inner diameter of the inlet path isgreater than an internal diameter of the fine channel, and the innerdiameter of the inlet path increases gradually with increasing distancefrom a position where the inlet opening and the inlet path interconnectwith each other, or remains identical with increasing distance from theinterconnection position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view showing the most basic fine channelshape according to the present invention.

FIG. 2 is a schematic plan view showing one example of fine channelshape according to the present invention.

FIG. 3 is a schematic plan view showing one example of fine channelshape according to the present invention.

FIG. 4A is a schematic illustration showing one example of fine channelshape according to the present invention.

FIG. 4B is a schematic plan view showing an enlargement of one portionof FIG. 4A.

FIG. 5 is a schematic perspective view showing the assembly process forone example of a fine channel shape used in an example 3 of the presentinvention.

FIG. 6 is a schematic perspective view of a quartz conduit pipetypically used for activating or decomposing gases.

FIG. 7A is a schematic perspective view showing a case in which at leastone section of metal is disposed inside either all, or a portion, of afine channel.

FIG. 7B is a schematic perspective view showing a case in which at leastone section of metal is disposed inside either all, or a portion, of afine channel.

FIG. 7C is a schematic cross-sectional view along the line A-A′ of FIG.7B.

FIG. 7D is a schematic perspective view showing a case in which at leastone section of metal is disposed inside either all, or a portion, of afine channel.

FIG. 7E is a schematic cross-sectional view along the line B-B′ of FIG.7D.

FIG. 8 is a schematic perspective view of a fine channel device used inan example 1.

FIG. 9A is a schematic perspective view of a fine channel device used inan example 2.

FIG. 9B is a schematic plan view showing an enlargement of one portionof FIG. 9A.

FIG. 10 is a schematic illustration showing one example of theapplication of the fine channel device used in the example 2 to a CVDapparatus.

FIG. 11 is a schematic cross-sectional view of a fine channel of thefine channel device used in the example 3, viewed along the line C-C′ ofFIG. 5.

FIG. 12 is a schematic illustration showing one example of theapplication of the fine channel device used in the example 3 to a CVDapparatus.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention relates to a fine channel device containing aplurality of fine channels for conducting gas treatments such aschemical reactions, with a fine channel shape that distributes the gasequally to the plurality of fine channels, and also relates to a gastreatment apparatus that uses this fine channel device to conductchemical reactions, particularly gas activation, decomposition, mixing,or reaction or the like, within the fine channels.

The inner diameter of the inlet path is greater than that of the finechannels, and either increases gradually, or remains identical, withincreasing distance from the position where the inlet opening and theinlet path are interconnecting with each other. As a result, gas can bedistributed equally to the plurality of fine channels disposed in eithera planar or three dimensional arrangement within the fine channeldevice, and two or more gases can also be mixed. Furthermore, a catalystor metal may also be disposed inside either all, or at least a portion,of each fine channel. The catalyst may be either a metal or a compoundthat contains a metal. By using the metal as a catalyst and/or a heater,or using the metal as an electrode for electrical discharge, theintroduced gas can be activated, decomposed, and/or reacted. Theinventors discovered that this enabled the aforementioned problemsassociated with the conventional technology to be resolved, and werehence able to complete the present invention.

As follows is a more detailed description of the present invention.Preferred embodiments of the present invention are described withreference to the drawings, but the present invention is in no waylimited to the examples presented below. For example, suitablecombinations of different structural elements of the different examplesare also possible.

First is a description of feeding a gas equally through a plurality offine channels, using a fine channel device of the present invention.

A fine channel device of the present invention has an inlet opening forintroducing a gas and an inlet path interconnecting with this inletopening, fine channels that interconnect with the inlet path and areused for distributing and feeding the gas equally, a discharge path thatinterconnects with each fine channel and is used for discharging thegas, and a discharge opening interconnecting with this discharge path.The inner diameter of the inlet path is greater than the inner diameterof the fine channel, and either increases gradually, or remainsidentical, with increasing distance from the position where the inletopening and the inlet path are interconnecting with each other. In thosecases where the diameter increases, it may either increase in a stepwisemanner, or increase in a cone-like manner, and an appropriate shape canbe selected in accordance with the conditions.

Here, the most basic outline of a fine channel device of the presentinvention is shown in FIG. 1. An inlet opening (1) for introducing a gasis provided at one end of an inlet path (3), and fine channels (4) withinner diameters (channel widths) that are smaller than that of the inletpath are provided. A discharge opening (2) is provided at the end ofeach fine channel (4). In this description, the term fine channel refersto a channel with an inner diameter of no more than approximately 500μm. Furthermore, the term inlet path refers to a channel with an innerdiameter larger than 500 μm but no more than several cm, and preferablyno more than 1 cm. In the present invention, in those cases where thecross-section is not circular, the term inner diameter is defined asbeing the inner diameter of the circular cylinder with the samecross-sectional area. Furthermore, the cross-sectional shape of thechannels in the present invention may be any shape, althoughsemicircular or rectangular shapes are preferred. There are noparticular restrictions on the inner diameter of the channel connectingthe inlet opening and the inlet path, although an inner diameter ofapproximately the same size as that of the inlet path is preferred.

There are no particular restrictions on the positioning of the finechannels, provided they are positioned at a different location from theinlet opening, and interconnect with the inlet path. Specifics of thisrequirement are described using FIG. 1. FIG. 1 is a fine channel devicecontaining n fine channels, from a fine channel Y₁ positioned closest tothe inlet opening, through to a fine channel Y_(n) positioned farthestfrom the inlet opening, each of which interconnects with the inlet path.The position at which the inlet opening interconnects with the inletpath is labeled X₀ (for reasons of simplicity, as shown in the figure,the point at which the center line of the inlet opening intersects withthe wall of the inlet path is represented by X₀), the position at whichthe fine channel Y₁ interconnects with the inlet path is labeled X₁ (asshown in the figure, the point at which the center line of the finechannel intersects with a line that corresponds with the wall of theinlet path is represented by X₁), and the length along the inlet pathbetween the interconnection position X₀ and the interconnection positionX₁ is labeled a₁. Furthermore, each of the interconnection positions,fine channels, and distances between fine channels are labeled insequence, so that the position at which the fine channel Y_(n), which isfarthest from the inlet opening, interconnects with the inlet path islabeled X_(n), the fine channel that is one position closer to the inletopening than the fine channel Y_(n), is labeled Y_(n-1), the position atwhich the fine channel Y_(n-1) interconnects with the inlet path islabeled X_(n-1), and the length along the inlet path between theinterconnection position X_(n-1) and the interconnection position X_(n)is labeled a_(n). In order to enable equal distribution of the gas tothe fine channels from Y₁ to Y_(n), the fine channels are preferablyarranged so that a₂ to a_(n) are equal. In addition, by making a₁ toa_(n) equal, this effect can be further improved.

However, in the present invention, the fine channels may also bearranged in positions in which a₂ to a_(n) are not equal, and thelengths between adjacent interconnection positions can be appropriatelyselected or altered in accordance with the materials used, and theproduction conditions and the like. For example, configurations in whichthe length either increases or decreases sequentially from a₁ to a_(n)are also possible.

Furthermore, in this type of fine channel device, the fine channeldevice may comprise either 1, or 2 or more fine channel substrates withfine channels. Furthermore, a structure in which a plurality of inletpaths are provided on a substrate(s), and these inlet pathsinterconnects each other in a fine channel substrate(s), and thereforein fine channels, is also possible.

FIG. 2 to FIG. 5 are schematic illustrations showing a number ofembodiments of the present invention. As already mentioned above, thepresent invention is in no way limited to these examples, and it shouldbe understood that various modifications are possible without departingfrom the spirit or scope of the present invention.

FIG. 2 is an example in which the inner diameter of the inlet path (3)increases gradually with increasing distance from the interconnectionposition of the inlet opening (1). The ratio in which thecross-sectional area of the inlet path, wherein the cross-section isperpendicular to the direction of travel, increases can be selected asdesired. Although a preferred ratio of change varies in accordance witha linear function from the minimum cross-sectional area of the inletpath through to the maximum cross-sectional area. In the presentinvention, the cross-sectional shape of the inlet opening is preferablycircular, although any other shape can also be selected. Suitable shapesinclude circular, elliptical, semicircular, square shapes and the like.

FIG. 3 is an example in which fine channels (4) labeled from Y₁ to Y_(n)are drawn from two inlet paths (3) and then merge in a series ofY-shaped arrangements. Using the fine channel device shown in FIG. 3, byintroducing gases that are to undergo a chemical reaction or gases thatare to be mixed into the two inlet paths respectively, the gases can bedistributed equally to the plurality of Y-shaped fine channels.Accordingly, the chemical reaction or mixing can be conducted under thesame conditions within all of the fine channels.

FIG. 4A is an example in which three fine channel devices (6) containingfine channels (4) are arranged vertically with respect to a single inletpath (3), so that the surface of each structure is perpendicular to thelong axis direction of the inlet path, and is positioned with aspecified separation from the adjacent structure. The inlet opening (1)is provided in the upper portion of the inlet path (3). As shown in FIG.4B, each of the fine channel devices shown in FIG. 4A is a fine channeldevice (6) containing fine channels (4) that are positioned with equalspacing along the inlet path (3). Dividing the inlet path (3) into twoseparate stages, is possible according to the present invention.Furthermore, in the present invention, the fine channel device (6) canbe structured as a type of fine channel (4). Accordingly, theconfiguration of FIG. 4A can be considered one example of theconfiguration of FIG. 1.

FIG. 5 is an example of a fine channel device (6) in which an uppercover (16), comprising an inlet opening (1) and an inlet path (3) formedon a circular disc-shaped substrate, a fine channel substrate (8),comprising a plurality of fine channels (4) that interconnect with theinlet path of the upper cover and are arranged radially around acircular disc-shaped substrate which has the same size as the uppercover, and a lower cover (17), comprising a plurality of dischargeopenings (2), which interconnect with the fine channels, formed in acircular disc-shaped substrate of the same size as the upper cover, arebonded together.

The type of fine channel substrate containing fine channels describedabove can be produced by any appropriate method, and suitable examplesinclude direct processing of a substrate material such as quartz,ceramic, silicon, metal, or resin using a technique such as mechanicalprocessing, laser processing, or etching. Furthermore, if the substratematerial is ceramic or resin, then the fine channel substrate can alsobe prepared by molding, using a casting mold of a metal or the like thatincludes fine channel shapes. Generally, a fine channel device describedabove is used with a cover bonded to the fine channel substrate. Themethod used for bonding the cover and the fine channel substrate canemploy the bonding method best suited to the substrate material used.For example, in those cases where the substrate material is a ceramic ormetal, methods that use solder or adhesives are used, in the cases wherethe substrate material is quartz or resin, thermocompression bonding isused, by applying a load under high temperature conditions within arange from 100° C. through to a temperature several hundred degreeshigher than 1000° C., and in those cases where the substrate material issilicon, a method is used in which the substrate surface is activated bywashing, and bonding is then conducted at room temperature. The finechannel substrate may be any color, and may be naturally colored,artificially colored, transparent, or translucent. If transparent, thenthe interior of the substrate can be checked visually, and if colored,then deterioration or reaction of the materials inside the substrate dueto the action of light can be prevented.

As follows is a description of a treatment apparatus, that uses a finechannel device of the present invention to effect the mixing,activation, decomposition or reaction of gases introduced into the finechannels.

The treatment apparatus of the present invention is a gas treatmentapparatus comprising a fine channel device described above, and conduitpiping that interconnects with the aforementioned inlet opening and isused for feeding the gas. By using a treatment apparatus with this typeof structure, gas can be distributed equally within the fine channeldevice portion, and a superior treatment apparatus that incorporates theconduit piping for feeding the treatment target gas to the fine channeldevice can be realized. Accordingly, treatments such as mixing,activation, heating, or decomposition of the gas and the like can beconducted efficiently and precisely. In the case of activation ordecomposition of a gas, normally a conduit pipe (10) for introducing gassuch as that shown in FIG. 6, made of quartz or the like and with a pipediameter (5) within a range from several cm to approximately 20 cm(specifically, from 1.0 to 1.5 cm for example), and a pipe length (9) ofapproximately several dozen cm (specifically, from 15 to 20 cm forexample) is heated from externally with a heating device or member suchas a heater (15). In this case, the surface area per unit volume (thespecific surface area) for the contact between the heated quartz conduitpipe and the gas, assuming the pipe diameter is 5 cm and the pipe lengthis 20 cm, is 80 m⁻¹ (formula: internal surface area of the pipe/pipevolume). In contrast, the surface area per unit volume (the specificsurface area) of the fine channels of a quartz fine channel device suchas that shown in FIG. 4( b), comprising, for example, 10 fine channelswith a width and depth of 500 μm and a channel length of 20 cm is 8000m⁻¹ (formula: internal surface area of the channels/channel volume). Asa result, if the respective times taken for a gas to pass through theconduit pipe of FIG. 6 and the fine channel device of FIG. 4( b) are thesame, then because the specific surface area over which the heatedquartz and gas make contact of the fine channel device is 100 timeslarger than the specific surface area for the conduit pipe, the heatingefficiency of the fine channel device is approximately 100 times that ofthe conduit pipe. Accordingly, the gas can be activated or decomposedapproximately 100 times more quickly. On the basis of this result, it isclear that a relatively short fine channel length is able to achieve asimilar level of activation or decomposition to a conduit pipe of thesize described above. If the fine channel width and depth describedabove are used, then the length of the fine channels need only be around200 μm. Consequently, by using the present invention, a device foractivating or decomposing gases can be reduced in size dramatically.

Furthermore, in a fine channel device or gas treatment apparatus of thepresent invention, as shown in FIG. 7A, at least one portion of metal(18) may be disposed along either all, or one or more portions, of thewalls of the fine channel (4). In this description, disposing metalinside a fine channel may refer to inserting a metal wire, with adiameter that is no more than the internal diameter of the fine channelor with a diameter that is capable of being inserted inside the channel,as shown in FIG. 7A, or may also refer to using a conventional methodsuch as deposition, sputtering or CVD or the like to form a thin metalfilm along either all, or one or more portions, of the walls of the finechannel (4), as shown in FIG. 7B and FIG. 7C, as well as FIG. 7D andFIG. 7E. Furthermore, the metal is preferably a material that exhibits acatalytic effect in activating or decomposing a gas, and moreover, ametal that when placed inside the fine channel can also be used directlyas a heater, by heating the metal, is particularly desirable. Examplesof this type of metal, for example for the activation or decompositionof N₂O (nitrous oxide) or NH₃ (ammonia) gases, include platinum,tungsten, molybdenum, tantalum, titanium, ruthenium, palladium, andchromium. At least one energy generating member for imparting energy tothe catalyst may be incorporated in the present invention.

Devices such as the apparatus and method used for heating the metal mayalso involve providing a heating device such as a heater, outside eitherthe fine channel device or the gas treatment apparatus, and then heatingthe metal inside the fine channels, thereby heating the gas introducedinto the fine channels. Furthermore, heating may also be conducted byconnecting the metal disposed on the inside walls of the fine channelsof the aforementioned fine channel device or gas treatment apparatuswith at least one current generation member or device (power supply)used for generating a current, and then causing a current to flowthrough the metal, or by using electromagnetic induction to generate aneddy current within the metal, thereby causing heating. By using suchtechniques, a metal catalytic effect can be added to the increase inheating efficiency achieved through the large specific surface area ofthe fine channels, meaning even more efficient activation,decomposition, mixing, reaction of gases or the like can be carried out.In the present invention, the term device may include apparatus,methods, processes, members, or portions or the like.

Furthermore, as shown in FIG. 7D and FIG. 7E, by disposing metal in anumber of locations on separate portions of the internal walls of finechannels within the fine channel device or gas treatment apparatus, andthen applying a potential difference across the separate sections ofmetal to generate an electric field therebetween, electrical discharge(plasma generation) can be achieved within the gas inside the finechannels, thereby enabling activation, decomposition, mixing, orreaction of introduced gases.

Furthermore, the fine channel device or gas treatment apparatus of thepresent invention may also include at least one voltage generationdevice for generating an electric field between the sections of metaldisposed at separate locations on the walls inside the fine channels.Typically, if a 10 mm gap is provided between sections of metal undernormal atmospheric conditions, then electrical discharge can be achievedby applying a potential difference between the sections of metalequivalent to a direct current of approximately 10 KV. In such a case,the electric field between the metal sections is 1×10⁶ V/m. In the caseof a fine channel according to the present invention, if the distancebetween the metal sections shown in FIG. 7D, namely the depth of thefine channel, is 10 μm, then in order to achieve an electric field of1×10⁶ V/m, an approximately 10 V direct current power source isrequired. In contrast with the power source apparatus required togenerate a direct current high voltage of 10 KV, in the presentinvention, one or several dry cells can be used to generate the directcurrent 10 V that is required for the present invention. Accordingly, inthe present invention, the voltage supply apparatus can be simplifiedsignificantly, and yet electrical discharge still generated within thefine channels, enabling the activation, decomposition, mixing, orreaction of the introduced gases.

In this manner, by using a fine channel device or gas treatmentapparatus according to the present invention, treatments such as themixing, activation, decomposition, or reaction of gases can be conductedwith comparative ease.

Specifically, in the case of activation of a gas, the gas is introducedinto the fine channels of the aforementioned fine channel device, theintroduced gas is heated, and/or a voltage is applied across theplurality of metal sections disposed inside the fine channels, therebycausing electrical discharge within the gas (generation of a plasma) andenabling the gas to be activated.

Furthermore, a gas that has been activated inside the fine channels of afine channel device or gas treatment apparatus according to the presentinvention may also be brought into contact with a substrate providedoutside the fine channel device or gas treatment apparatus. This contactcan be used to form a uniform film, by forming a film derived from theactivated gas on the substrate.

In addition, the introduced gas can also be decomposed or reacted byeither heating, or passing a current through the gas. Accordingly, afine channel device or gas treatment apparatus of the present inventionis preferably a fine channel device that includes a heating deviceoutside of the fine channel device, for heating the gas introduced intothe fine channels. Furthermore, in the case of heating, the fine channeldevice and the conduit pipes used in the present invention arepreferably produced from quartz glass, and even more preferably fromsynthetic quartz glass, and particularly high-purity synthetic quartzglass, in order to enable the fine channel device to withstand hightemperatures, specifically temperatures of 1000° C. or higher.

Furthermore, a fine channel device or gas treatment apparatus of thepresent invention can also be used as a reactor for gas-phase reactions.One specific example is a reaction technique wherein benzene and ammoniagases are introduced into the fine channels, and the aforementionedmetal catalyst such as platinum or tungsten is heated, eitherelectrically or from externally, to increase the catalytic efficiency,thereby enabling aniline to be synthesized directly. If a fine channeldevice of the present invention is used for a chemical reaction in thismanner, then a reaction field with a restricted space can be providedinside the fine channels, thereby increasing the collision frequency ofthe reactants and improving the reaction efficiency. Furthermore, theadvantage of the characteristics of the fine channels can be usedsufficiently by the present invention, for example, such as synthesis ofthe target material can be conducted in a very short time period withina range from several microseconds to several milliseconds, even ifreactants that are extremely difficult to activate, or reactants thatare unstable, are used for a reaction.

In addition, in the case of mixing two or more different gases, mixingcan be achieved, for example, by introducing the gases into the finechannel device shown in FIG. 3, and then bringing the gases into contactwith each other.

There are no particular restrictions on the gases that can be used inthe treatments described above, provided the treatment does not departfrom the spirit or scope of the present invention. Examples of suitablegases include tetraethoxysilane (Si(OC₂H₅)₄), dichlorosilane (H₂SiCl₂),and nitrogen. Furthermore, nitric oxide or ammonia can be used, and bothof these gases can also be used at the same time.

A fine channel device of the present invention includes an inlet openingfor introducing a gas and an inlet path interconnecting with this inletopening, fine channels that interconnect with the inlet path and areused for distributing and feeding the gas equally, a discharge path thatinterconnects with each fine channel and is used for discharging thegas, and a discharge opening interconnecting with this discharge path.In addition, the inner diameter of the inlet path is greater than thatof the fine channel, and either increases gradually, or remainsidentical, with increasing distance from the position where the inletopening and the inlet path are interconnecting with each other. By usingsuch a structure, the gas can be distributed equally to each of the finechannels.

Furthermore, there are no particular restrictions on the positioning ofthe fine channels, insofar as they interconnect with the inlet path at adifferent location from the inlet opening. Specifics of this requirementare shown in FIG. 1, which shows a fine channel device containing n finechannels, from a fine channel Y₁ positioned closest to the inlet openingthrough to a fine channel Y_(n) positioned farthest from the inletopening, each of which interconnects with the inlet path, wherein if theposition at which the inlet opening interconnects with the inlet path islabeled X₀, the position at which the above fine channel Y₁interconnects with the inlet path is labeled X₁, the length along theinlet path between the interconnection position X₀ and theinterconnection position X₁ is labeled a₁, and thereafter each of theinterconnection positions, fine channels, and distances between finechannels are labeled in sequence, so that the position at which the finechannel Y_(n) farthest from the inlet opening interconnects with theinlet path is labeled X_(n), the fine channel that is one positioncloser to the inlet opening than the fine channel Y_(n) is labeledY_(n-1), the position at which the fine channel Y_(n-1) interconnectswith the inlet path is labeled X_(n-1), and the length along the inletpath between the interconnection position X_(n-1) and theinterconnection position X_(n) is labeled a_(n), then in order to enableequal distribution of the gas to the fine channels from Y₁ to Y_(n), thefine channels are preferably arranged so that a₂ to a_(n) are equal. Inaddition, by making all of a₁ to a_(n) equal, this effect of enablingequal distribution to each of the fine channels can be further improved.

Furthermore, in this type of fine channel device, the fine channeldevice may comprise either 1, or 2 or more fine channel substrates withfine channels. Furthermore, a structure in which a plurality of inletpaths are provided on the substrate, is also possible. These inlet pathsmay interconnects each other in a fine channel substrate(s), andtherefore in fine channels. So doing enables the treatment of a largevolume of gas.

Furthermore, another aspect of the present invention is a gas treatmentapparatus comprising a fine channel device described above, and conduitpiping that interconnects with the aforementioned inlet opening and isused for feeding the gas. By using a treatment apparatus with this typeof structure, gas can be distributed equally within the fine channeldevice portion, a treatment apparatus incorporating the fine channeldevice, and the conduit piping for feeding the target gas to the finechannel device, can be produced, and treatments such as mixing,activation, heating, or decomposition of the gas and the like can beconducted.

Furthermore, in a fine channel device or gas treatment apparatus of thepresent invention, at least one section of metal may be disposed alongeither all, or one or more portions, of the walls of the fine channels.The metal is preferably a material that exhibits a catalytic effect foractivating or decomposing a gas, and moreover, a metal that when placedinside the fine channel can be used directly as a heater by heating themetal is particularly desirable. By using such a configuration,treatments such as activation, decomposition, mixing, or reaction of thegas or the like can be conducted even more efficiently. Examples of thistype of metal, include iron, tungsten, molybdenum, tantalum, titanium,and vanadium, and of these, the use of tungsten is particularlypreferred.

Furthermore, as a devices for heating the metal in the presentinvention, at least one heating device such as a heater, may be providedoutside either the fine channel device or the gas treatment apparatus.By heating the metal inside the fine channels, the gas introduced intothe fine channels may be heated. Alternatively, heating may also beconducted by connecting the metal disposed on the inside walls of thefine channels of the aforementioned fine channel device or gas treatmentapparatus with at least one current generation member or device (powersupply) used for generating a current, and then causing a current toflow to heat the metal. Furthermore, heating may also be conducted byusing electromagnetic induction to generate an eddy current within themetal, thereby causing heating. By using such techniques, a metalcatalytic effect can be added to the increase in heating efficiencyachieved through the large specific surface area of the fine channels,meaning even more efficient activation, decomposition, mixing, orreaction of gases can be carried out.

Furthermore, metal may also be disposed in a number of locations, namelytwo or more locations, on separate portions of the internal walls offine channels within the fine channel device or gas treatment apparatus,and a potential difference then applied across the separate sections ofmetal to generate an electric field therebetween. By so doing,electrical discharge (plasma generation) can be achieved within the gasinside the fine channels, thereby enabling activation, decomposition,mixing, or reaction of introduced gases.

Furthermore, the fine channel device or gas treatment apparatus of thepresent invention may also include a voltage generation device forgenerating an electric field between the sections of metal disposed atseparate locations on the walls inside the fine channels. By using sucha configuration, a power source in the order of several V can be used tocause an electrical discharge within a fine channel with a width ofseveral dozen μm to several hundreds of μm, thereby enabling activation,decomposition, mixing, or reaction of introduced gases. In the presentinvention, it is possible to simplify a voltage supply device. Specificexamples for those values that are not restricted for the fine channelsof the present invention are presented below. The width of the finechannels of the present invention are, for example, within a range from10 to 500 μm, and preferably from 20 to 200 μm, and even more preferablyfrom 50 to 100 μm. The height of the fine channels of the presentinvention are, for example, within a range from 1 to 100 μm, andpreferably from 10 to 50 μm, and even more preferably from 20 to 30 μm.

Moreover, the length of the fine channels of the present invention are,for example, within a range from 0.1 to 20 cm, and preferably from 1 to10 cm, and even more preferably from 3 to 5 cm.

Furthermore, a fine channel device or gas treatment apparatus of thepresent invention is preferably a fine channel device that includes aheating device provided outside of the fine channel device for heatingthe gas introduced into the fine channels. Furthermore, the fine channeldevice and the conduit pipes may be formed from any material, althoughformation from fused quartz glass, synthetic quartz glass, or compositequartz glass or the like is preferred. In order to enable the finechannel device to withstand high temperatures, specifically temperaturesof 1000° C. or higher, when heated, the fine channel device and conduitpipes of the present invention are preferably formed from high-puritysynthetic quartz glass. By using such a configuration, the introducedgas can be heated, and either decomposed or reacted.

EXAMPLES

As follows is a description of examples of the present invention. Asalready mentioned above, the present invention is in no way limited tothe examples presented below, and it should be understood that variousmodifications are possible without departing from the spirit or scope ofthe present invention.

Example 1

A fine channel device (6) such as that shown in FIG. 8 was prepared as afirst example. Blast processing was used to form an inlet path (3) witha width of 2 mm and a depth of 500 μm, and 10 fine channels (4), each ofwhich interconnects with the inlet path, and has a width of 500 μm, adepth of 500 μm, and a length of 15 cm that includes turn-back positionspartway along the fine channel, in a quartz substrate with dimensions of70 mm×50 mm, and a depth of 1.65 mm. The distance between adjacentinterconnection positions, where the 10 fine channels and the inlet pathinterconnect with each other, was 2 mm. Another quartz substrate of thesame size as this fine channel substrate (8) was used as a cover (7),and was bonded to the fine channel-containing surface of the finechannel substrate by thermal bonding, thus producing a fine channeldevice.

Using a feed pump, N₂O was introduced into the inlet opening (1) of thefine channel device at a flow rate of 10 L/minute, 10 flow rate meterswere positioned at the discharge openings of the 10 fine channels, andthe discharge flow rate from each fine channel was measured. N₂O wasdischarged from each fine channel with a flow rate within a range from0.9 to 1.1 L/minute, confirming that the N₂O was flowing equally througheach fine channel.

Example 2

A fine channel device (6) such as that shown in FIG. 9A was prepared asa second example. In FIG. 9, three of the fine channel devices shown inFIG. 8 are used. These three fine channel devices all interconnect withthe inlet path (3), and are positioned with a 5 cm spacing between thestructures. Tungsten wire (12) with a diameter of 0.3 mm is disposedinside the fine channels of these fine channel devices, as shown in FIG.9B. The fine channel device of the FIG. 9A was placed inside a CVDapparatus (13) such as that shown in FIG. 10, and heated using a heater(15) provided at a furnace of the CVD apparatus. The inside of the CVDapparatus furnace was then evacuated down to 0.3 Torr with a vacuumpump. The heater material was a kanthal material. Subsequently, NH₃ gaswas introduced through the gas inlet opening at a flow rate of 10L/minute, forming a SiN film on the surface of Si wafer substrates (14)of diameter 3.5 inches. The Si wafer substrates were positioned 10 mmbelow the fine channel devices, and 1 mm away from the dischargeopenings of the fine channel devices. The heater temperature was from1000 to 1100° C. (a temperature (slow cooling point) slightly lower thanthe temperature of 1100 to 1200° C., at which internal strain within thequartz can be removed in 15 minutes), lower than the softening point ofquartz (1600 to 1700° C.), enabling the formation of an extremelyfavorable SiN film with very few film defects. Furthermore, the filmthickness of the SiN film formed on each of the three Si wafers was from5 to 7 nm, and extremely uniform films were able to be formed. In thisexample, the fine channel devices are heated from externally using theheater of the CVD apparatus. However, by connecting the tungsten wiredisposed inside the fine channels to a power source, and then eithercausing a direct current to flow through the wire, or generating eddycurrents through electromagnetic induction, the tungsten wire itselfcould also be used as the heater.

Example 3

A fine channel device (6) such as that shown in FIG. 5 was prepared as athird example. The fine channel substrate was produced by using blastprocessing to form 18 fine channels of width 500 μm, depth 10 μm, andlength 30 mm in a radial pattern in the surface of a quartz substratewith a diameter of 5 inches and a thickness of 1 mm. A through hole ofdiameter 1 mm was provided at the fine channels, in order to enableinterconnection between the inlet path of the upper cover (16), thechannel, and the discharge opening of the lower cover (17).

Furthermore, the upper cover (16) was formed from a quartz substrate ofthe same size as the fine channel substrate, wherein an inlet opening(1) of diameter 2 mm was provided in the center of the substrate, and aninlet path (3) formed from a circular cylindrical concave portion ofdiameter 110 mm and depth 300 μm, and 18 distribution channels (19) thatextend in a radial manner were formed by blast processing.

Furthermore, the lower cover (17) was also formed from a quartzsubstrate of the same size as the fine channel substrate, wherein acircular cylindrical concave portion of diameter 50 mm and depth 300 μmwas formed in the center of the substrate, and 18 recovery channels (20)were also provided. Blast processing was used to form 18 radiallypositioned through holes of diameter 1 mm in the bottom surface of theconcave portion as gas discharge openings.

The fine channel device was formed by bonding the upper cover, the finechannel substrate, and the lower cover together using thermal bonding.

Furthermore, as shown in simplified form in FIG. 11, a film of platinum(11) of thickness 100 nm was formed by sputtering in at least onelocation on the upper and lower surfaces of the fine channels. Theplatinum film formed on the upper surface was connected to a directcurrent 10 V power supply via a connection switch, and the platinum ofthe lower surface was grounded. Fine channel devices of thisconstruction were placed inside a CVD apparatus (13) such as that shownin FIG. 12. The inside of the CVD furnace was then evacuated down to 0.3Torr with a vacuum pump. Furthermore, the inside of the CVD furnace washeated to 300° C. using the heater (15). Subsequently, NH₃ gas wasintroduced through the gas inlet opening at a flow rate of 5 L/minute,forming a SiN film on the surface of Si wafer substrates (14) ofdiameter 5 inches. The Si wafers were positioned 10 mm below the finechannel devices. At the same time that introduction of the NH₃ gas wascommenced, a voltage was applied to the platinum electrode on the uppersurface inside the fine channels, thereby causing electrical dischargeinside the fine channels, and enabling the formation of extremelyfavorable SiN films with very few film defects and with a film thicknessof about 5 to 7 nm.

INDUSTRIAL APPLICABILITY

The present invention can provide a fine channel device in which a gascan be distributed equally to a plurality of fine channels disposed ineither a planar or three dimensional arrangement. Furthermore, theinvention also can provide a gas treatment apparatus that uses this finechannel device and enables the treatment of gases, including activation,decomposition, mixing, and reaction and the like, to be conducted moreefficiently than has conventionally been possible.

1. A fine channel device comprising: at least one inlet openingintroducing a gas, at least one inlet path interconnecting with theinlet opening, at least one fine channel, which interconnects with theinlet path and distributes and feeds the gas equally, a discharge pathwhich interconnects with the fine channel and discharges the gas, and atleast one discharge opening interconnecting with the discharge path;wherein an inner diameter of the inlet path is greater than an internaldiameter of the fine channel, and the inner diameter of the inlet pathincreases gradually with increasing distance from a position where theinlet opening and the inlet path interconnect with each other.
 2. A finechannel device according to claim 1, wherein the fine channel devicecontains n fine channels, from a fine channel Y₁ positioned closest tothe inlet opening through to a fine channel Y_(n) positioned farthestfrom the inlet opening, each of which interconnects with the inlet path;and a₂ to a_(n), which are lengths along the inlet path between theinterconnection positions, are all equal, when a position at which theinlet opening interconnects with the inlet path is labeled X₀, aposition at which the fine channel Y₁ interconnects with the inlet pathis labeled X₁, a length along the inlet path between the interconnectionpositions X₀ and X₁ is labeled a₁, and thereafter each interconnectionposition, fine channel, and distance between fine channels is labeled insequence, so that a position at which the fine channel Y_(n) farthestfrom the inlet opening interconnects with the inlet path is labeledX_(n), a fine channel that is one position closer to the inlet openingthan the fine channel Y_(n) is labeled Y_(n-1), a position at which thefine channel Y_(n-1) interconnects with the inlet path is labeledX_(n-1), and a length along the inlet path between the interconnectionpositions X_(n-1) and X_(n) is labeled a_(n).
 3. A fine channel deviceaccording to claim 1, wherein a metal is disposed on all, or at least aportion of, walls of the fine channel.
 4. A fine channel deviceaccording to claim 3, wherein the fine channel device comprises at leastone current generation device for causing current to flow through themetal disposed on a wall of the fine channel device.
 5. A fine channeldevice according to claim 3, wherein the fine channel device comprisesat least one voltage generation device for generating an electric fieldbetween sections of metal disposed in separate locations on walls of thefine channel device.
 6. A fine channel device according to claim 1,wherein the fine channel device comprises heating device providedoutside the fine channel device, for heating a gas introduced into thefine channel.
 7. A gas treatment apparatus, comprising a fine channeldevice according to claim 1, and conduit piping which interconnects withthe inlet opening and is used for feeding gas.
 8. A gas treatmentapparatus according to claim 7, wherein the fine channel device and theconduit piping are formed from synthetic quartz glass.
 9. A gastreatment apparatus according to claim 7, wherein a metal is disposed onall, or at least a portion of, walls of the fine channel, and furthercomprising at least one current generation device for causing current toflow through the metal.
 10. A gas treatment apparatus according to claim7, wherein a metal is disposed on one or more walls of the fine channel,and further comprising at least one current generation device forcausing current to flow through the metal.
 11. A gas treatment apparatusaccording to claim 7, further comprising at least one heating deviceprovided outside the fine channel device, for heating a gas introducedinto the fine channel.
 12. A gas treatment apparatus according to claim7, wherein the gas is at least one of nitric oxide and ammonia.
 13. Agas treatment apparatus according to claim 7, wherein a catalyst isdisposed on all, or at least a portion of, walls of the fine channel.14. A gas treatment apparatus according to claim 13, wherein thecatalyst is a metal or a compound that comprises a metal.
 15. A gastreatment apparatus according to claim 13, further comprising at leastone energy generation device for providing energy to the catalyst.
 16. Agas treatment apparatus according to claim 13, wherein the gas is atleast one of nitric oxide and ammonia.